Fibrinolysin therapy of thrombophlebitis and pulmonary embolism--a double-blind study.

Thrombophlebitis and pulmonary embolism are major causes of disability and death in both medical and surgical patients. Etiological factors are still poorly understood. Preventive measures as currently practised are non-specific and based on questionable premises. Diagnostic measures to predict the silent fatal embolus are inadequate. Currently accepted treatment measures are designed to prevent extension of the thrombus but have no effect on the existing clot. Theoretically, thrombolytic preparations now being marketed offer some hope for dissolution of preformed thrombi. An experimental study was carried out on artificially induced thrombi in jugular and femoral veins of mongrel dogs. Human fibrinolysin (Actase, Ortho) was infused locally and systemically in varying doses. No thrombi were successfully lyzed by either method. Thirty-six cases of acute deep thrombophlebitis in the leg, one of axillary thrombosis, three of chronic postphlebitis of a lower limb with massive edema and eight of pulmonary emboli were observed and carefully documented clinically. All these patients received anticoagulants unless there was a contraindication. Fibrinolysin infusions in varying dosages were administered to 27 patients; 10 served as controls. The observers were unaware of the identity of those receiving the actual drug or of those given the placebo until completion of the study. Progress of the disease was judged by the rate of dis-appearance of symptoms and signs. No significant benefit could be noted in the treated as compared to the control group, in terms of rate of recovery or incidence of embolus.